Following Donald Trump's threat in August to retaliate against North Korean nuclear tests "with fire and fury", it cannot come as much surprise that the US military's latest nuclear review appears to be more aggressive than its predecessors. The previous one was conducted in 2010.

Trump’s Nuclear Posture Review (NPR), published yesterday, highlights a need for the country to modernise its nuclear capabilities and loosen constraints on their use as global threats have “worsened markedly”.

“While the United States has continued to reduce the number and salience of nuclear weapons, others, including Russia and China, have moved in the opposite direction,” the document reads.

It goes on to cite North Korea’s “illicit pursuit” of nuclear weapons and Iran’s capability to produce them within one year as further reasons which drive the Pentagon’s more hawkish nuclear ambitions.

Among the proposals is to widen the circumstances in which their military can launch a nuclear attack.

As well as retaliating in kind to a nuclear offensive, the document states that nuclear weapons could be used in response to a non-nuclear attack causing mass casualties, or which is aimed at critical infrastructure or nuclear command and control sites.

An earlier draft of the NPR indicated that cyberattacks could be grounds for a nuclear response.

But while that idea has been made deliberately ambiguous in the final report, it means the US could be first to launch a nuclear attack in a conflict.

The ultimate form of retaliation

The review also calls for the development of new “low-yield” atomic warheads that can “penetrate adversary defenses", adding that it would counter a US-held belief that Russia deems their weapons as too big to be used, making them less effective as a deterrent.

"Our strategy will ensure Russia understands that any use of nuclear weapons, however limited, is unacceptable," the document reads.

Modernising and boosting funding for the military’s aging nuclear arsenal is also proposed in the review.

“Over half of NNSA’s (National Nuclear Security Administration) infrastructure is over 40 years old, and a quarter dates back to the Manhattan Project (World War II) era,” the document reads.

It estimates that the cost of upgrading the nuclear cache could amount to 6.4 percent of the current defence budget, which is $574.5 billion (€460.9 billion) for the current fiscal year.

The nuclear review sparked an angry response from the Russian government on Saturday, who deemed it “bellicose” and “anti-Russian”.

"We must take into account the approaches that are now circulating in Washington and take necessary measures to ensure our security," the foreign ministry added.

The proposals were also slammed by the head of the Arms Control Association, who dubbed plans to develop new types of nuclear weapons as “dangerous, Cold War thinking”.

“The use of even a small number of these weapons would be catastrophic,” writes Daryl Kimball on the Arms Control Today website.

“Threatening nuclear attack to counter new kinds of ‘asymmetric’ threats is unnecessary, would increase the risk of nuclear weapons use, and would make it easier for other countries to justify excessive roles for nuclear weapons in their policies.”